Texas Instruments LM3S1911-IQC50-A2T

Overview

LM3S1911-IQC50-A2T from Texas Instruments is a 32-bit ARM Cortex-M3 microcontroller with 256 KB flash, 32 KB SRAM, and integrated peripherals including UART, I²C, SSI, GPIO, timers, watchdog, analog comparators, and hibernation module. It operates at up to 50 MHz, supports 3.3 V supply, and targets embedded control in space-constrained industrial and consumer systems.

For engineers reviewing the LM3S1911-IQC50-A2T datasheet, LM3S1911-IQC50-A2T pinout, LM3S1911-IQC50-A2T application, or LM3S1911-IQC50-A2T equivalent, key selection criteria include its 100-pin LQFP package, hibernation-capable real-time clock, 50 MHz CPU frequency, and lack of on-chip USB or Ethernet PHY - requiring external interface components for those functions.

Technical Context

The LM3S1911-IQC50-A2T implements the ARMv7-M architecture with NVIC-based interrupt handling, SysTick timer, and Memory Protection Unit (MPU). It integrates a hibernation module with battery-backed RTC and SRAM, enabling ultra-low-power wake-up from deep sleep states using external pins or time events.

Peripherals are memory-mapped and accessed via APB bus; clock gating is supported per peripheral block. The device lacks floating-point unit (FPU), DSP extensions, or TrustZone security, and does not support Thumb-2 IT blocks for conditional execution outside core instructions.

Key Specifications

Pinout & Package

LM3S1911-IQC50-A2T is housed in a 100-pin LQFP package with exposed thermal pad. Pin assignments follow TI's standardized Stellaris signal mapping, supporting multiplexed GPIO, peripheral functions, and dedicated power/ground terminals.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar microcontroller applications.

Compared with TM4C123GH6PM and STM32F103VCT6, the LM3S1911-IQC50-A2T offers proven low-power hibernation and simpler peripheral integration but lacks USB, CAN, and floating-point capability - making it optimal for cost-sensitive, battery-operated control nodes without advanced interface requirements.

Availability

LM3S1911-IQC50-A2T is available at Aetrix Electronics and suitable for industrial sensor nodes, smart thermostat controllers, LED lighting dimming modules, and factory floor I/O terminals requiring stable component supply and long-term lifecycle support.

Supply support for LM3S1911-IQC50-A2T includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Texas Instruments is a global semiconductor company headquartered in Dallas, Texas, specializing in analog, embedded processing, and wireless technologies since 1930.

The Stellaris LM3S series was designed as an early ARM Cortex-M3-based MCU family targeting cost-effective, low-power industrial and consumer control applications before the TM4C migration.

FAQ

What is the maximum operating frequency of the LM3S1911-IQC50-A2T?

The LM3S1911-IQC50-A2T operates at a maximum CPU frequency of 50 MHz. This rating is specified under full voltage (3.0–3.6 V) and ambient temperature (–40°C to +85°C) conditions per the TI SPMS032I datasheet. The 50 MHz limit applies to the Cortex-M3 core and all synchronous peripherals; exceeding this frequency may cause timing violations or undefined behavior in the LM3S1911-IQC50-A2T.

Does the LM3S1911-IQC50-A2T include a hardware floating-point unit?

No, the LM3S1911-IQC50-A2T does not include a hardware floating-point unit (FPU). It implements the ARM Cortex-M3 core without the optional FPU extension. All floating-point operations must be performed in software using the standard C library or CMSIS-DSP routines. This design choice reduces die size and power consumption, consistent with the LM3S1911-IQC50-A2T's focus on deterministic real-time control rather than computationally intensive signal processing.

What package type is used for the LM3S1911-IQC50-A2T?

The LM3S1911-IQC50-A2T is packaged in a 100-pin LQFP (Low-Profile Quad Flat Package) with 0.5 mm pitch and 14 mm × 14 mm body size. It includes an exposed thermal pad on the underside for improved heat dissipation. This package is RoHS-compliant and compatible with standard PCB assembly processes, including reflow soldering and automated optical inspection - confirmed in the TI SPMS032I datasheet Section 15 "Pin Diagram".

Can the LM3S1911-IQC50-A2T operate from a single 3.3 V supply?

Yes, the LM3S1911-IQC50-A2T can operate from a single 3.3 V supply, provided that VDD, VDDA, and VDDC are all supplied at 3.3 V ±5%. The device does not integrate a voltage regulator, so external decoupling (e.g., 100 nF ceramic + 4.7 µF tantalum per supply rail) is required near each VDD pin. This configuration is validated in TI's recommended power circuit for the LM3S1911-IQC50-A2T and supports full 50 MHz operation across the industrial temperature range.

Is the LM3S1911-IQC50-A2T still in active production by Texas Instruments?

Texas Instruments discontinued the LM3S1911-IQC50-A2T in 2015 as part of the transition to the TM4C series. However, Aetrix Electronics maintains legacy inventory and provides extended lifecycle support, including traceable sourcing, obsolescence mitigation planning, and cross-reference assistance for migration to TM4C123GH6PM or other qualified alternatives - ensuring continuity for existing LM3S1911-IQC50-A2T-based designs.